Fastening device



May 7, 1945. G. A. TINNERMAN FASTENING DEVICE Original Filed June 26, 1942 Fig. Z

Patented May 7,1946

George A. Tinnerman, Cleveland, Ohio. assigner to Tinnernian Products, Inc.,

a corporation of Ohio Original application June 26, 1942, Serial. No. and this ary 18, 1944, Serial No. 522,558 y Y 4 Claims. (Cil 85-32) 448,592. Divided This application is a division of my copending application 448,592, filed June 26, 1942, which latter application is a continuation in part of application 340,203, illed June 12, 1940, now Patent No. 2,326,903, issued August 17, 1943.

This invention `relates to a fastening device for screw threaded shafts for use where it is desired to eiect a helical engagement in a thread groove as a nut and also to maintain a frictional engagement with the crests of the thread. The invention is especially useful in connection with various instruments having screw-threaded adjustments, for `instance, tuning or similar devices in radio apparatus. Such instruments frequently include a coil form or the like and an adjusting screw providing for axial adjustment of the tuning core within the coil form.

My invention provider in a very simple manner for maintaining a frictional engagement with the crests of the threaded adjusting screw, preventing its jarring loose, where the screw carries an electric current, my frictional clamp is of further advantage in preventing leakage or irregularities from movement of the screw in the nut. My invention is particularly useful in radio apparatus mounted on automobiles or other 1ocations where it is subjected to constant vibration, tending to disturb the adjustment and interfere with the reception.

To the above ends, I have provided a simple device which furnishes at once a nut by means of warped edges engaging in the groove ofthe thread and spring tongues projecting from the same device, but positioned so as not to interfere with the nut members, extending parallel with the axis of the screw and engaging crests of its threads to maintain a friction tight engagement therewith.

In the drawing, Fig. 1 is a sectional elevation of an instrument mounting embodying one form of my fastening device; Fig. 2 is a section taken on the line 2--2 on Fig. 1; Fig. 3 is an enlarged view of the mounting for the adjusting screw shown in Fig. 1; Fig. 4 is a sectional plan of the mounted fastener shown in Fig, 3; Fig. 5 is a sectional plan showing the lower arm of the fastener of Fig.l 3 in position, the plane of the section being just below the upper arm, as indicated by the line 5 5 on Fig. 3.

As shown in Fig. 1, A illustrates a coil or other instrument in the form of a cylinder housing a tuning core B which has an axially extending threaded operating shaft b. The cylinder A is held on a suitable support C in any suitable manner.

56 this purpose.

I have shown the lustrum supportl by means of ab d duced endsdoccupying pe and havingV agscrew-y., Y with obliquei'tonguves 4"d ppos i u thereof. These tongues are cut from t of the strip and bent up d warped at their' edges, s a screw thread, and, act" a a screw isindicatedfat ing upwardly through jthem bridge piece, it locks thy in a very simple manner, Figs. 1 and 2; v

The screw shaft b of Fig. having' a screw driver slot b' in its upper end. Accordingly, by providing a supporting nut for it the core B may be readily moved axially in the cylinder. However, support by an ordinary nut is not satisfactory, where an accurate adjustment should be maintained, especially if the instrument is liable to receive vibration. My device, about to be described, and as herelnbefore outlined, not only provides the nut but also frictional engagement for maintaining a tight connection.

As shown in Figs. 1 and 3, I0 indicates my combined nut and frictional engager, shown as a strip doubled into a U-shape and snugly embracing a supporting arm 20. Each arm of the U has an opening for the passage of the threaded shank b. One of the arms, preferably the lower arm Il, is equipped with warped surfaces about the opening to engage within the thread groove and act as a nut. As shown, this warped surface comprises an upstanding inwardly flanged nearly annular portion l2, the edge I3 of which forms a nearly complete helical turn, as shown, especially in Figs. 3 and 5.

On opposite sides of the opening through the upper arm l5, I provide a pair of parallel iiat tongues I 6 which are formed from the body of this arm by parallel slits l1. These tongues lie on diametrically opposite sides of the screw threaded shaft and extend nearly at right angles to the arm but normally converge slightly so as to form a friction-tight .engagement with the crests of the threads, as shown particularly in Figs. 1, 3 and 4.

The combined nut and frictional retainer above described, may be mounted on the supporting plate 20 simply by spreading the arms of the fastener apart. shoving it over the edge of the support until the upstanding helical portion i2 extends into the opening 2l made in the support for This eifectively positions the iasithold theshaft against any inadvertent dis-- placement. They may also be availed of whenever desired for maintaining s tightelectrle connection between the supporting member Il and theshaft. Thisisofspecialvalueinsometypes of radio apparatus.

Itwillbeseenthatmyfasteningdevicemay be made of a single strip of resilientsheet material simply by cutting and bending operations.

The device provides a passageway for a threaded bolt and twosets of engaging devices coacting with such bolt, one set occupying the thread groove of the bolt to act as a nut, the other set engaging crests oftheboltthreadtoholdthebolt frictionally against vibration or displacement in the nut.

I claim:

1. A fastening device comprising s strip oi sheet material doubled on itself in the U-form, a nut carried by one arm of the fastener and extending toward the other arm and means on the other arm to frictionaily press against the crest of the thread of a boit carried by the nut arm.

2. A fastener comprising a U-shaped strip of metal having a pair of parallel arms, aligned 35 asoasss openingsthroughthetwoarmathemetslofone oftbearmsbeingdistortedtowardtheothersrm toprovideanupstanding helicaledgebetweenthe armsandtheothersrmcarryingopposedspring tongues, each frictionaliy englglnl aplurality of crestsofthe thresdoftheboltoccupyingtbe openings.

3. A U-shaped fastener having its arms adapted to frictionally engage the topand bottom oi a support, one arm of the fastener being provided with sn opening and an upward and inwardly extending helical flange about the opening. said flangebelngadaptedtooccupytheopeningoi the support, and the other arm of the fastener having an opening and s. pair of dlametricaily opposedtonguesonoppositesidesoitheopening extending at approximately right angles to that arm but slightly converging to lie with spring pressure against a plurality of crests of a bolt threaded through the nut of the first arm.

4. A one-piece fastener of sheet material comprising s base portion having an opening for the passage of a threaded shank, and a top portion formed by bending the base portion upwardly and inwardly to present a portion overlying the base portion and spacedtherefrom, the top portion surrounding the shank and having an opening registering with the opening of the base, the material of the top portion being diverted on opposite sides of the shank to provide projecting portions adapted to frictionally engage the crest of the thread without acting as a nut, the material of the base portion being diverted upwardly and. 

